The method for determination of the exact allergen concentration in Dirofilaria immitis was reported. The highly purified allergen obtained from D. immitis was repeatedly injected to rats with Freund's complete adjuvant and the monospecific antibody against the allergen was got from the rats hyperimmunized. The present experiment showed that the method of single radial immunodiffusion by the use of the monospecific antibody against the allergen determined the exact allergen concentration. The area ƒÎR2 of a precipitation circle, which developed in anti-allergen serum-containing agar gel layer when allergen diffused into this layer, was proved to be directly proportional to the amount of the allergen used.

Experimental Acanthamoeba keratitis was induced in 24 female Dutch rabbits to examine the clinical effects of infecton in the eye and to study the usefulness of a new histopathological technique for evaluating rabbit models of this infection. One eye of each animal in group A or B received an instillation of 1.3×104 (group A) or 1.3×105 (group B) amoeba cysts/eye; phosphate-buffered saline (PBS) solution was instilled into the contralateral eye as the control; animals in groups C and D received intrastromal injections of 5.0×103 (group C) or 1.5×104 (group D) cysts/eye in one eye and injection of an equal volume of PBS in the contralateral eye. Animals were observed daily for 5 to 84 days. Two rabbits in group D were killed on day 5 and enucleated eyes were embedded in paraffin and stained with hematoxylin-eosin or iodine-potassium iodide. In groups A and B, clinical signs of corneal injury disappeared by 4 hours after inoculation and signs of infection disappeared by day 2. In contrast, all eyes that had been injected with Acanthamoeba (groups C and D) developed severe keratitis, including keratoneuritis and corneal ulcer, followed by neovascularization or corneal perforation. Histologic examination showed infiltrates of leukocytes, lymphocytes, eosinophils, plasmacytes and spindle-shaped cells. The most extensive cell infiltration, and also exocytosis, liquefaction degeneration and intrastromal trophozoites, were seen in th limbic conjunctiva and palpebral conjunctiva. In addition, there was evidence of migration of inflammatory cells to the ciliary body and intravitreal space. This study showed that injection of Acanthamoeba into corneal stroma causes severe infection of the cornea and other eye tissues and that iodine-potassium iodide staining of paraffin embedded specimens is useful to detect Acanthamoeba trophozoites and cysts.

Immunocompetent BALB/c mice are resistant to infection with Brugia pahangi (B. pahangi). In mice treated with a single dose of carrageenan (CGN) or promethazine (PMZ) at an early stage of infection, adult worms and microfilariae were recovered at 12 weeks post-inoculation (PI) with third-stage infective larvae (L3); neither was recovered from control mice. To observe local cellular responses in CGN-treated, PMZ-treated and control mice, we investigated the peritoneal cavities on days 4, 8, 12 and 14 PI. In control mice, larvae were encapsulated by peritoneal exudate cells (PEC) from day 4 PI; morphological observations showed the macrophages and eosinophils were involved with rapid and intense cellular reactions to the larvae. The PEC count was significantly lower in CGN-treated than in control mice on days 8 and 12 PI. The eosinophil content in the PEC of the CGN-treated mice was 0% on days 4, 8 and 12 PI and the larvae were not surrounded by PEC, while it was significantly lower in PMZ-treated mice than in control mice on days 8 and 12 PI; larvae were surrounded by PEC from day 8 PI. The rate of recovery of living larvae was significantly higher in CGN-treated or PMZ-treated mice than in control mice on day 14 PI. These results suggest that the resistance of mice to B. pahangi infection may be determined by early-stage cellular reactions to the larvae; blocking the functions of macrophages and/or eosinophils at this stage may increase susceptibility to infection.

We developed a new screening kit for the detection of anti-Toxocara larval excretory-secretory antibodies. The test can be performed within 3 min for one sample and does not require a high-priced supplemental instrument. Moreover, results are easily and directly observed. Using this test kit, 22 sera taken from healthy subjects were negative for anti-Toxocara larval excretory-secretory antibodies at the serum dilution of 1:20. Of 14 proven cases of parasitic infections other than toxocariasis, one (gnathostomiasis) showed a positive result, but the others were negative. In serologically diagnosed toxocariasis, the test kit showed good correlation with ELISA, immunoblot and double gel diffusion tests. We designated this test kit as ToxocaraCHEK.

In order to identify the eosinophil hyporesponsiveness factor in the microfilaremic host, stage-specific monoclonal antibodies against microfilariae (Mf) of Brugia pahangi were produced. One of these (MfG2a) was established for the first time as a monoclonal antibody of IgG2a isotype against Mf. MfG2a recognizes the eosinophil hyporesponsiveness factor, the 42 kDa excretory/secretory antigen of Mf. Treatment of MfG2a significantly (P < 0.05) induced eosinophil response with rapid reduction of microfilaremia in previously Mf injected mice which became amicrofilaremic within 2 weeks. Eosinophil hyporesponse was observed in the control microfilaremic mice and the microfilaremia persisted at high levels. Another monoclonal antibody, MfG1 of the IgG1 class, recognized the 64-kDa surface antigen of Mf, MfG1 was less effective in eosinophil response- or microfilaremia reduction. These data suggest that the 42-kDa microfilarial excretory/secretory antigen might be responsible for the eosinophil hyporesponsiveness in B. pahangi Mf injected mice.

Each year 10 million Japanese travelers and workers visit various foreign countries, including Asia and Africa. Sexually transmitted diseases (STD) s are now more common in many developing countries than in the developed nations (De Schamphelerie et al., 1990; Mosha et al., 1993; Nkowane, 1991) . Evidence indicates that the classic STDs facilitate the transmission of human immunodeficiency virus (HIV) infection (Pepin et al., 1989). Particularly compelling is the need to prevent fetal death, prematurity, and neonatal complications by STDs, especially in developing countries (Schulz et al., 1987) . Whereas many studies have been conducted on the prevalence of STDs in urban populations of developing countries, data are sparse on their prevalence in rural areas, there is little reliable information on the risk of STDs especially in the developing countries. This is because most studies on the prevalence of STDs have been conducted in selected populations, such as inpatients or outpatients being administered medical treatment for the infection. The true prevalence of STDs can be derived only from data on unselected

We made a comparative study on serum biochemical values of mature Mongolian gerbils between the wild-colored (agouti) and the coat color mutants of both sexes by autoanalyzers. The coat colors of the mutants were white spotted-agouti, albino, black and white spotted-black. All of serum biochemical values we measured of different coat color gerbils were not significantly different each other. We did not find any lipemic sera and any hyperglycemia in all coat color gerbils. Compare to the other common laboratory rodents, patterns and values of serum protein fractions of the gerbils were different. Namely, A/G ratios and rates of y-globulin fraction of gerbils were much higher than those of mice and rats and were the same as those of human beings.

Antibody, production in Mongolian gerbils (Meriones unguiculatus) immunized with crude extract of Dirofilaria immitis adult worm was tested with passive cutaneous anaphylaxis reaction. Immunized gerbils produced a long-term binding, heat-labile antigen-specific antibody which sensitized the rat skin. Those profiles were like an IgE antibody. In an intact gerbil, IgE-like substance was detected in an immediate intracutaneous reaction with anti-rat IgE antibody. Mast cells representing metachromasia were confirmed in the skin tissue section of Mongolian gerbils stained with Toluidine blue and were thought to be target cells for those anaphylactic reactions.

We investigated the capacity of excretory and secretory antigen (ES) derived from living filarial worms in the induction of CD23 expression on human peripheral blood T cells by using flow cytometry. ES (10 μg/ml) significantly induced the expression of CD23 on human T cells. Moreover, increased CD23 expression was completely abolished by preincubation with specific antibody to ES. The results suggest that ES might play a certain role in IgE antibody production by induction of CD23 expression on T cells.

In order to know the basic nature of the various color mutants of the gerbil as the susceptible host to filarial infection, the growth curve as well as food and water consumption volume and reproduction rates were compared among coat color mutants of the Mongolian gerbil, such as agouti, white spotted-agouti, albino, black and white spotted-black type mutants.There was almost no significant difference in growth curve and reproduction rates among the color mutants. Namely, mean weights of these newborns and of matures among these gerbils were 3.0 g, and 60 g in male or 52 g in female respectively, and the mean number of newborns among mutants was 4.2 to 4.8. However, the periods of delivery among these mutants varied to wide ranges. As the reasons of the change of the delivery periods, it was considered that the post-partum oestrus occurred in some of the gerbils, and in these gerbils, the delayed implantation of the placenta were seen relatively often and also in some gerbils, the irregular oestrus cycle was existed.In addition, some genetic studies on coat colors were carried out. It appeared that some genes controlling coat colors exist in the gerbils as in mice or rats, and it suggested that albino and black colors are controlled by autosomal ressesive genes.The coat color mutants of the gerbils also will be useful animal as the susceptible host to filarial infection.

The quality of drinking water in various regions of Indonesia was surveyed and the results of bacteriological studies during the last 5 years were summarized. The following results were obtained. 1. The quality of drinking water of Indonesia became better a slight since 1982, but the mean positive rates in the number of total colonies and coliform group counts did not become so good. 2. Among the strains detected, Klebsiella pneumoniae, Enterobacter cloacae, Enterobacter aerogenes and Citrobacter freundii were frequently detected each year. Escherichia coli was found in 8 water samples in 1979, 7 samples in 1980 and 5 samples in 1982. From the tap water in Jakarta, Escherichia coli was detected in 3 samples in 1979, and 2 samples in 1982. Among the bacteria related to the enteric bacteria, Pseudomonas aeruginosa and Aeromonas hydrophila were frequently detected. These bacterial strains detected showed no difference among the areas and the sources of the water samples. 3. It is noteworthy that Salmonella E1 group was detected in 1 samples from each of well water in 4 islands, and Salmonella C1 group in 1 sample from Jakarta.

The number of Japanese stayed in tropical countries is increasing, as the Japanese technical cooperation with the countries is improved.The diseases from which Japanese suffers in these countries are infectious hepatitis, especially type A, amoebic as well as bacillary dysentery, typhoid fever, various kinds of intestinal helminthiasis and so on.These diseases are though to be orally infected, and among sources of infection, the drinking water is considered to be most important as the main route of infection.From 1977, we started to examine the drinking water at various places in tropical countries.Results were shown that almost all water samples contained a large amount of coli form bacilli and were polluted by faeces and sewage.The degree of the pollution of water samples was proved to be highest in samples from Indonesia, Thailand and the Philippines of Southeast Asia, Pakistan of Southwest Asia, Iraq of Middle East, Kenya, Mozambique and Neigeria of Africa, Mexico of Central America, and Ecuador and Peru of South America.The residual chlorine as a bactericide was observed in the drinking water from Singapore and Malaysia, and some samples from Egypt and Panama, but, in the water samples from the other parts of tropical countries, no residual chlorine was found at all.

A blood-sucking leech, Hirudo nipponia Whitman, at the early stage was found at the conjunctiva of the left eye of a 63-year-old woman, which caused a heavy lacrimation and a sense of the foreign body without pain. The leech was removed with forceps after it was anesthetized with 0.4% narcotic benoxyl given in the eye. Symptoms on the part of the eye completely ceased after the leech was removed. It is assumed that the leech infestation occurred in a paddy field during her working there.

フィラリアの旧流行地, 長崎県・五島の2地区住民のフィラリア抗体価を調べた。フィラリア抗体価は, 血清をアニサキス抗原で吸収後, 犬フィラリア抗原による間接赤血球凝集反応で求めた。一方, 同一血清について, 成人T細胞白血病ウィルスに対する抗体価 (ATLA抗体価) を螢光抗体法で調べた。ATLA抗体陽性者群のフィラリア抗体価は, いずれの地区においても陰性者群の抗体価より有意に高く, この傾向は住民の各年齢層でみられた。また, 過去において確実にフィラリア仔虫を有していた人達のATLA抗体陽性率は, 同地区の住民より高く, 特に女性の場合は, はるかに高い陽性率を示した。以上の事実から, フィラリア感染は, ATLVのウイルス血症発現に何らかの意味で関与していることが推察される。

The method for determination of the exact allergen concentration in Dirofilaria immitis was reported. The highly purified allergen obtained from D. immitis was re- peatedly injected to rats with Freund's complete adjuvant and the monospecific antibody against the allergen was got from the rats hyperimmunized. The present experiment showed that the method of single radial immunodiffusion by the use of the monospecific antibody against the allergen determined the exact allergen concentration. The area ƒÎR2 of a precipitation circle, which developed in anti-allergen serum-containing agar gel layer when allergen diffused into this layer, was proved to be directly proportional to the amount of the allergen used.